Pump for liquid fuel and other liquids



Sept. 11, 1934.

F. J. s. JQNES PUMP FOR LIQUID FUEL AND OTHER LIQUIDS Filed Feb.- 16,1933 wM m 0. WW 0/@ m m r MW an Patented Sept. 11, 1934 UNITED STATESPUMP FOR LIQUID FUEL AND OTHER LIQUIDS Francis Joseph Stawell Jones. I

Porthcawl, Wales Application February 16, 1933, Serial No. 657,082

in Great Britain December 5, 1932 8 Claims. (Cl. 103-150) My presentinvention relates to improvements in and connected with pumps for liquidfuel and other liquids and of the type which will automaticallyaccommodate itself to vary the supply 3 according to the requirements orrate of consumption of the consuming unit. For this purpose, myinvention is particularly useful in connection with the feeding ofliquid fuel in internal combustion engines. A form of liquid fuel pump10 heretofore proposed employs a diaphragm which is flexed backwards andforwards at its axis, its periphery being fixed between annularorcircular fastening members, its axis having secured to it an axiallyreciprocating rod slidable through a 1! guide, the diaphragm beingoperated in a chamber having valve controlled inlet and exhaust ports.In such an arrangement owing to the diaphragm being fixed at itsperiphery between im- 7 movable bodies and its axis to a uni-axiallysliding rod, the nature of its motion is necessarily limited to areciprocation of its axis solely in an axial direction, which in onedirection is effected by a compression spring and in the other by apositive pull on the said rod. Consequently, in

order to obtain automatic accommodation of the pump to the requirementsof the consuming unit, for example an internal combustion engine, amechanical lost motion device is incorporated in the mechanicalconnection of the said rod to the operating unit which may be a camdriven from the engine. The object of my present invention is to obtaina simple method of obtaining automatic accommodation of the pump to therequirements of the consuming unit. A further object of my invention isto obviate the necessity of com- '40 manufacture of liquid fuelpumps-for'internal combustion engines and other liquid fuel con sumingunits requiring an automatically controlled pump feed.

Broadly my present invention is characterized in that the liquid raisingand impelling or liquid transferring means of the pump is such that whenthe supply of liquid reaches the stage when it would exceed theimmediate-demand of the consuming unit, the movable element of the pumpitself is influenced by the pressure of liquid in the pump in suchmanner that; without altering its connection to its prime mover itreduces its own periodicity of effective operative motion. By this meansthe nature of the mechanical connection of, for example, the diaphragmof 9, diaphragm pump to a prime mover can always remain unaltered, i. e.the necessity of a declutching device, mechanical lost motion device orother mechanism other than that appropriate merely for the normalpumping operation of the pump, is eliminated.

Briefly, one form of my invention consists in providing a diaphragmpump, in which the diaphragm is shaped and constructed to follow anoscillating motion imparted by a primemover to a member"operatively-connected to the' diaphragm, the nature and extent ofoscillation of the diaphragm varying automatically proportionally to theresistance of the pumped liquid, the arrangement being that the rate ofdelivery of the liquid is determined by the freedom of oscillationpermitted thev diaphragm by the reactance of the liquid in the pump.

In order that my invention may be clearly understood and readily carriedinto effect, I have appended hereto a sheet of drawings illustratingembodiments thereof and wherein,

Fig. l is a sectional side elevation view of one embodiment.

Fig. 2'is a sectional end elevation view on the line 2a--2a of Fig. 1.

Fig. 3 is a detail sectional side elevation view showing a slightmodification.

Referring to the drawing, a liquid fuel or other liquid pump of a likenature or entailing like requirements comprises a diaphragm l immovablysecured at its periphery but secured within its periphery between a pairof plates 2 and 3 to the outer 2 of which is affixed an arm 4, thediaphragm 1 being shaped to permit oscillation of said arm, said arm 4being adapted to be oscillated from a prime mover for example a cam 5 orother mechanically equivalent device whereby the diaphragm is flexedabout a point on the periphery of the inner plate 3 of said plates, suchpoint be- 95 ing slightly translatively moved away from the pump body bythepressure of liquid in the pump when such pressure reaches apredetermined degree so as to automatically reduce the degree ofoscillation of the diaphragm.

In practice the periphery of the diaphragm 1 can be gripped between apair of annular cupped members 6 and '7, one of which indicated by thereference numeral 6 is a flanged or flared enlargement or uni-lateralprojection of a body 8 provided: with valve controlled inlet and outletpassages 9 and 10 respectively for the liquid, said diaphragm extendingacross and closing a chamber ll common to both of said passages.

A substantially cylindrical metal block can form passed a screw 17threaded in to the lower endof said tail, the head of this screwpressing wash-.

ers 18 against the boss 16, and a washer 19 being pressed between therim of the vessel and a flange 20 integral with the body 8. The crosssection of said vessel can be cylindrical or recti linear to correspondwith that of the said metal body, the rim of the said vessel abuttingagainst the base of said body.

Extending laterally into the said body is an in- I let passage 21 (seeFig. 2) near the base of the body and communicating with said vessel 15at its inner end by means of an opening 22 in the base of the said body.A tubular flltr 23 is fitted, preferably with a clearance, around thesaid tail so that on the suction stroke of the diaphragmthe liquid isdrawn through the filter into the said bore or vertical passage.

Between the rim of the annular cup shaped flange 6 and the shallowcupped annular cap '7 is as before mentioned gripped the periphery ofthe diaphragm and the appropriate gripping action is effected. by boltsor screws 24 passed through. the-outer parts of the said cup shapedchamber and cap. The said chamber 11 which is preferably ,a cylindricalconcentric. bore of the body 8 accommodates for most of its length acoiled tension spring 25 secured at one end to a diametrically disposedpin 26 in a screwed boss 27 on which is screwed-a plug'or cap 28 and atits other end to a"pin 29 inside a hollow boss 30 formed integral withthe annular cupped disc 2- which asshown can be a flange on one end ofthe operating rod 4. The periphery of this disc 2 slightly clears theinner periphery of the said annular cap 7 and'the annular shallowcylindrical disc 3 is abutted against the inner face of the diaphragm bythe influence of the spring 25. This shallow cylindrical disc 3 has acentral boss or a nut 31a threaded on to the inner endof the said hollowboss 30 which passes through the said diaphragm, and a point on its rimis adapted to form the centre of oscillation of the diaphragm,

- by reason of such rim being abutted against an annular surface 31 inthe block or body 8 of the pump. When the reactance of pressure ofliquid in the pump exceeds a predetermined degree, for example when thesupply of fuel in the carburettor reaches maximum storage this disc 3 isurged outwards by the pressure of liquid and thereby the centre ofoscillation of the diaphragm is moved outwards translatably producing anidling or floating like motion of the diaphragm upon the cushion ofliquid in the chamber 11 so that no liquid is drawn up or forced out ofthe pump until there is a further demand from the carburettor.

From the foregoing, it will be understood that the pump is actuated byoscillation of the diaphragm which can be oscillated by movement of saidrod in any radial direction by any suitable mechanism thereby obtaininga form of universal connection between prime mover and pump.

Where the said vertical bore 13 in the said tail meets the saidintersecting bore a non-return disc valve 32 or other one way valve isprovided so that liquid will not flow back down the said tail when oncedrawn into the chamber 11. The liquid is forced out from the chamber 11to an outlet pipe 33, a union 34 for such a pipe and a nonretum discvalve 35 or other suitable valve is provided in the pipe or union, thevalve 35 only permitting the liquid to flow out of the chamber 11.

The diaphragm can be of metal but it is preferred to make it of a fairlythick flexible composition known as suitable for this purpose. Its

.arrangement and construction enables the rod connected to it to beoscillated in a universal manner so that the said rod bearsuni-laterally against the periphery of a rotating cam or it can beconnected to a small crank or eccentric for omratiom A cap nut threadedon to the lower end of said tail can be employed to hold the said flltervessel on the tail.

The cap 7 is preferably enlarged at diametrically opposite sides toprovide lugs 36 apertured to receive bolts for attaching the device toan engine or elsewhere.

In the foregoing arrangement, the inner disc 3 constitutes in efiect thebearing member about a point of which the desired oscillation isimparted. When dealing with normal liquids, the amount of frictionarising in this respect should not produce suflicient wear on thecontacting parts of the members, 3 and 6, but in order to eliminate riskof ineillciency through such wear, instead of the disc 3 constitutingthe bearing member, the outer disc 2 can constitute the. bearing member.A suitable method of efiecting this is shown in Fig. 3 in which the disc2 is made deeper and its rim flared to a U section as indicated at 2a,the edge of this rim being abutted by the tension of the spring 25against the cup shaped cap 7, the configuration of this cap 7 if desiredbeing modified so as to keep the axial dimension of the disc 2 withinreasonable limits, a suitable configuration of cap 7 being that shown inFig. 3. This particular arrangement is advantageous where the outer sideof the pump is exposed to lubricating oil, for example, on an internalcombustion engine the lugs 36 can be bolted to the crankcase which isapertured to allow the rod 4 to pass into the crankcasethe aperture inthe crankcase being sufficiently large to enable the oil in thecrankcase to be thrown on to the disc 2. Such an arrangement isadvantageous where the rod 4 is operated from a cam shaft or othersuitable rotating member inside the crankcase.

The diaphragm can be concentrically ridged as indicated at In in Fig. 3should a large angle of.

motion be required for imparting the desired oscillation.

What I claim is:--

1. In a pump, a diaphragm secured at its periphery, a member secured tothe diaphragm within such periphery and free to follow an oscillatingmotion, a suction and compression chamber one wall of which isconstituted by said diaphragm, means for connecting said member to aprime mover for oscillating such member and flexing the said diaphragmin accordance with the oscillation of said member, the arrangement beingthat the rate of delivery of the liquid is determined by the freedom ofoscillation permitted the diaphragm by the reactance of the liquid inthe said pump member.

2.A pump for liquid 'fuel and other liquids comprising a pump body openat oneside, a diaphragm secured at its periphery so as to close the openside of said body, a suction and compression chamber on one sideoi saiddiaphragm, a pair of plates secured against opposite faces of saiddiaphragm, one of said plates bearing against part of the pump body, andmeans for oscillating said plate about a point of its contact with saidbody.

3. A pump for liquid fuel and other liquids comprising a pump body openat one side, 9. diaphragm secured at its periphery so as to close theopen side of said body, a suction andcompression chamber on one side ofsaid diaphragm, a pair of plates secured against opposite faces*of saiddiaphragm, one of said plates bearing against part of the pump body, andmeans for oscillating.

said plate about a point of its contact with said body, and an armextending substantially axially from the outerof said plates and adaptedto be oscillated by a prime mover,

4. A liquid fuel or like pump comprising a pump body, an opening in oneside of said body, a

flexible diaphragm secured at its periphery so as to close saidopeningbut shaped so that it is free to be flexed within its periphery,a pair of discs secured against opposite sides of said diaphragm,

an arm extending from the outer of said plates, springmeans pressing one01! said discs against a seating on said body, means whereby said armcan be oscillated about a point on the peripheryof the said latter disc.

5. A liquid fuel or like pump comprising a pump body, an opening in oneside of said body, a

flexible'diaphragm secured atits periphery so as v to close said openingbut-shaped so that it is free to be flexed within its periphery, a pairof discs secured against opposite sides of said dia phragm, an armextending from the outer-of said plates, spring means pressing the outerof said discs against a seating on said body, means whereby said arm canbe oscillated about a point on the periphery of the said latter disc.

one side of the diaphragm within its periphery, a

6. A liquid fuel or like pump comprising a pump body, an opening in oneside of said body, a flexible diaphragm secured-at its periphery so asto close said opening but shaped so that it is free to be flexed withinits periphery, a pair of discs secured against opposite sides of saiddiaphragm, an arm extendingfrom the outer of said plates, spring meanspressing the inner' of said discs against a seating on said, body, meanswhereby said arm can be oscillated abouta point on the periphery of thesaid latter disc.

7. A pump for liquid fuel and other liquids comprising a body part, adiaphragm immovably secured at its periphery, a plate secured againstsuction and compression.chamber'onewall of which includes saiddiaphragmpa; coiled tension spring in said chamber, connectedito thediaphragm so as to press said'plate against said body part and an; armextending-tw n] plate and free to be oscillated. v

8. A pump for liquidyfuel andoth'er liquids open side or said body,a'sucti chamber on one side ,0! said diaphragni, a pair of platessecured against opposite,iacesaof-said' dia phragm, one of saidplatesbearing against part- I of the pump body, and meansffo illatin'gsaid plate about a pointio fits contact n aid body, and an armextendingsubstantially allyir'om the outer-of said platesand adaptedtobeoscillated by a prime mover, inlet and outlet passages to and fromsaid chamber, non-return valves in said' passages, a liquid receivingvessel carriedby said body part and receiving said inlet passage andmeans to connect said vessel to'a source of supply.

FRANCIS JOSEPH STAWELL JONES.

